A dormant feud between Dublin and Livermore over Doolan Canyon — a prized patch of unincorporated open space bordering both cities — may be reigniting, following Livermore’s recent push to bring the land under its sphere of influence.

“We were surprised by the move,” said Dublin Mayor Tim Sbranti, adding that Livermore’s city manager and mayor told his city in August of their intentions.

Not long after, Livermore’s planning commission voted unanimously to recommend the city council ask the Alameda County Local Agency Formation Commission to expand Livermore’s influence “sphere” to include 2,620 acres in Doolan Canyon — a move that often precedes annexation. The council will consider the recommendation on Sept. 12, said Livermore senior planner Steve Stewart.

“The protection of open space in Doolan Canyon has been a council priority for a number of years. We are very interested in including that land in … our sphere of influence,” said Linda Barton, Livermore city manager. She pointed to city efforts to purchase and preserve pieces of the property.

Livermore owns 125 acres on the east side of Doolan Road at the gateway to Doolan Canyon. The city also supported East Bay Regional Parks’ recent acquisition of the Schmitz property, a 633-acre stretch bordering Alameda and Contra Costa counties at the head of Doolan Canyon, Barton said.

Calling Livermore’s action “unilateral,” Sbranti said he was still hopeful a mutually agreeable solution for the land, believed to contain sensitive plant and wildlife habitat, could be reached.

“My goal is to find something that’s jointly beneficial to the two cities, the property owners (in Doolan Canyon) and Alameda County,” he said.

Livermore’s sphere of influence initiative is partly a reaction to Dublin’s own recent moves toward the canyon, Barton said.

In December, in response to a request from Doolan Canyon property owners, Dublin leaders began a study to consider whether to add 1,450 acres of the land to its planning area. The study would explore creation of new general plan land use designations and policies to guide future development of up to 1,990 residential units for active senior housing, preservation of open space, park provisions, major ridgeline protections, grading and other measures. It also would serve as the basis for a future application to LAFCO to include the property within Dublin’s sphere of influence, according to Livermore staff reports.

Livermore leaders say Dublin’s actions could threaten the open space, which has long been desired as a “greenbelt buffer” between the two cities. They point to a 2002 agreement signed by Livermore and Dublin officials formally acknowledging Dublin’s decision at that time to remove Doolan Canyon from its planning area.

The memorandum, Sbranti said, removed the land from Dublin’s planning area because in 2002 there were no plans for development there. But it did not mean that development of Doolan Canyon would never be discussed again, he said.

While he said he “wholeheartedly supports” the greenbelt concept, Sbranti said he believes the rights of property owners hoping to develop part of the land — which abuts Dublin’s border — should be considered, too. His city’s environmental work will help determine what, if any, of the sensitive area can be built upon, he added.

Acknowledging Livermore’s historically good working relationship with Dublin, Barton said, “We realized in sitting down with Dublin that their perception of what that memorandum meant and ours was different. But if there are options that would preserve the property and also meet some needs that Dublin has, we would certainly listen and discuss that.”